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1.
Sci Adv ; 9(9): eade2451, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36867690

RESUMO

The origins of horseback riding remain elusive. Scientific studies show that horses were kept for their milk ~3500 to 3000 BCE, widely accepted as indicating domestication. However, this does not confirm them to be ridden. Equipment used by early riders is rarely preserved, and the reliability of equine dental and mandibular pathologies remains contested. However, horsemanship has two interacting components: the horse as mount and the human as rider. Alterations associated with riding in human skeletons therefore possibly provide the best source of information. Here, we report five Yamnaya individuals well-dated to 3021 to 2501 calibrated BCE from kurgans in Romania, Bulgaria, and Hungary, displaying changes in bone morphology and distinct pathologies associated with horseback riding. These are the oldest humans identified as riders so far.


Assuntos
Domesticação , Humanos , Animais , Cavalos , Reprodutibilidade dos Testes , Mandíbula , Leite
2.
Anthropol Anz ; 76(3): 179-180, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31478054

Assuntos
Hominidae , Animais , Humanos
3.
Anthropol Anz ; 71(1-2): 57-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24818439

RESUMO

Sex diagnosis on human skeletal remains from forensic or archaeological contexts is often hampered by poor preservation or completeness. The successful application of most identification methods demands the presence of skull or pelvis, since most reliable sex-determining features can be found here; unfortunately, because of their fragile anatomy, these bones are frequently damaged or destroyed. To compensate for this, we tested the effectiveness of two often well preserved postcranial structures as instrument of sexing skeletal individuals. Preliminary results are promising.


Assuntos
Osso e Ossos/anatomia & histologia , Análise para Determinação do Sexo/métodos , Antropologia Física/métodos , Feminino , Humanos , Masculino
4.
Nature ; 502(7470): 215-8, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24108053

RESUMO

The discovery of quasicrystals--crystalline structures that show order while lacking periodicity--forced a paradigm shift in crystallography. Initially limited to intermetallic systems, the observation of quasicrystalline structures has recently expanded to include 'soft' quasicrystals in the fields of colloidal and supermolecular chemistry. Here we report an aperiodic oxide that grows as a two-dimensional quasicrystal on a periodic single-element substrate. On a Pt(111) substrate with 3-fold symmetry, the perovskite barium titanate BaTiO3 forms a high-temperature interface-driven structure with 12-fold symmetry. The building blocks of this dodecagonal structure assemble with the theoretically predicted Stampfli-Gähler tiling having a fundamental length-scale of 0.69 nm. This example of interface-driven formation of ultrathin quasicrystals from a typical periodic perovskite oxide potentially extends the quasicrystal concept to a broader range of materials. In addition, it demonstrates that frustration at the interface between two periodic materials can drive a thin film into an aperiodic quasicrystalline phase, as proposed previously. Such structures might also find use as ultrathin buffer layers for the accommodation of large lattice mismatches in conventional epitaxy.

5.
J Appl Genet ; 54(3): 309-25, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23553074

RESUMO

We applied, for the first time, next-generation sequencing (NGS) technology on Egyptian mummies. Seven NGS datasets obtained from five randomly selected Third Intermediate to Graeco-Roman Egyptian mummies (806 BC-124AD) and two unearthed pre-contact Bolivian lowland skeletons were generated and characterised. The datasets were contrasted to three recently published NGS datasets obtained from cold-climate regions, i.e. the Saqqaq, the Denisova hominid and the Alpine Iceman. Analysis was done using one million reads of each newly generated or published dataset. Blastn and megablast results were analysed using MEGAN software. Distinct NGS results were replicated by specific and sensitive polymerase chain reaction (PCR) protocols in ancient DNA dedicated laboratories. Here, we provide unambiguous identification of authentic DNA in Egyptian mummies. The NGS datasets showed variable contents of endogenous DNA harboured in tissues. Three of five mummies displayed a human DNA proportion comparable to the human read count of the Saqqaq permafrost-preserved specimen. Furthermore, a metagenomic signature unique to mummies was displayed. By applying a "bacterial fingerprint", discrimination among mummies and other remains from warm areas outside Egypt was possible. Due to the absence of an adequate environment monitoring, a bacterial bloom was identified when analysing different biopsies from the same mummies taken after a lapse of time of 1.5 years. Plant kingdom representation in all mummy datasets was unique and could be partially associated with their use in embalming materials. Finally, NGS data showed the presence of Plasmodium falciparum and Toxoplasma gondii DNA sequences, indicating malaria and toxoplasmosis in these mummies. We demonstrate that endogenous ancient DNA can be extracted from mummies and serve as a proper template for the NGS technique, thus, opening new pathways of investigation for future genome sequencing of ancient Egyptian individuals.


Assuntos
Embalsamamento/métodos , Metagenoma , Múmias , Sequência de Bases , Biópsia , Antigo Egito , Embalsamamento/história , Biblioteca Gênica , História Antiga , Humanos , Dados de Sequência Molecular , Filogenia , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/métodos , Temperatura , Toxoplasma/genética
6.
Chem Commun (Camb) ; 47(24): 6954-6, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21556415

RESUMO

Hydroxyl radical intermediates are trapped in calcined Cu/HY zeolites in the presence of oxygen and water. This suggests that hydrogen peroxide is formed in situ from oxygen. Brønsted acids enhance the formation of the radicals.

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